Karen Walker is Hawking Butter Substitute

Cher hawked Equal. Brooke Shields shows women how to restore eyelash length thanks to Latisse. And now Megan Mullally is the latest gay icon to sign up as a spokesperson, singing and dancing her way through an I Can't Believe It's Not Butter ad.

The actress, who won an Emmy as Karen Walker on Will & Grace, sings of hydrogenated oil and is wheeled around a supermarket on a jumbo tub of butter substitute.

Watch the ad here ... and click to the next page for clips of other gay icons selling things on TV.

Martha Raye for Polident

Cher for Equal

Sally Field for Boniva

Martha Stewart for Kmart

Madonna for Pepsi